Structural characterization of electrodeposited copper hexacyanoferrate films by using a spectroscopic multi-technique approach

A deep structural investigation predominantly by X-ray spectroscopic techniques is conducted on films of copper hexacyanoferrate (CuHCF) deposited under different conditions, aimed at establishing structure–properties relationships.
E. Giorgetti et al., Phys. Chem. Chem. Phys.  14, 5527 (2012).

The continuously growing interest devoted to Prussian Blue and related metal hexacyanoferrates is due to the large number of fields where they can find application, including electrochromism, electrocatalysis, ionic and electronic conductivity, charge storage, corrosion protection. A new experimental procedure, involving the Insertion of Cu2+ ions into previously deposited CuHCF film led to an increased response sensitivity. XAS has been used to establish a structure-properties relationship. Details about the local structure of copper hexacyanoferrate as well as about the oxidation state of copper during the intercalation process can be gained by XAS. Here we demonstrate that reliable structural information can be retrieved just using Cu K-edge data even for assessing the Fe–C distance in CuHCF samples which have been proved to be constituted of two phases, i.e., PB and CuHCF.

In fact, the typical structure of such compounds is characterized by alarge number of linear Fe–C–N–Cu chains, with a total length of ~5 Ang. , giving rise to an EXAFS scattering signal of high intensity due to the focusing and super-focusing effects. In addition, we have assessed  that different synthetic processes produce materials with different structure determining the location (interstitial or lattice) of intercalated copper ions which is still a debate in CuHCF based electrodes. Retrieve article Structural characterization of electrodeposited copper hexacyanoferrate films by using a spectroscopic multi-technique approach M. Giorgetti ,  L. Guadagnini ,  D. Tonelli ,  M. Minicucci, and G. Aquilanti Physical Chemistry Chemical Physics  14, 5527 (2012). 10.1039/C2CP24109A